Staple-driving machine



aan, zo, 1925.

F. POLZER S TAPLE DRIVING MACHINE Filed Dec. 18, 1922 ATTORN EY,

Patented Jan. 20, 1925.

UNITED STATES PATEgNTAoi-Flcn- FRIDOLIN POLZER, OF NORWALK, CONNECTICUT, ASSIGNOR TO THE E. H. HOTCHKISS COMPANY, F NORWALK, CONNECTICUT, .A CORPORATION 0F CONNECTICUT.

" STAPLE-DRIVING MACHINE.

Application led December 18, 1922.K Serial No. 607,525.

v To all whom t may ctn/mem.'

Be it known thatv I, FRIDoLIN PoLzEn, a citizenv of the United States, residing at -Norwalk, county of Fairfield, State of Connecticut, have invented an Improvement in Staple-Driving Machines', of which the following is a specification.

This invention relates to stapling machines and more particularly to that type known as strip staple machines wherein each staple at the time it is driven is severed from a strip of integrally connected staples which is fed forwardly at each operation of the machine to bring the staples succeively into a position to be severed and driven.

' It is an object of the invention to provide a construction which will sever and drive the -individual staples .and which will prevent clogging of the machine during the severing and driving operation.

It is also an object of the invention to pro- 4vide a construction which will free itself should a staple fail to be properly driven or should several "staples become wedged in the raceway or throat, so that there will be no clogging of the machine.

With the foregoing and other objects in view, I have devised the construction illustrated in the accompanying drawing, in which- Fig. 1 is a partial longitudinal section and partial side elevation of a stapling machine showing the elements 1n normal position ready for a staple driving operation.

Fig. 2 is a similar view showin the elements in the position they occupy Just prior to the staple severing operation.

. Fig. 3 is a similar view showing the position of the several elements at the completion of the staplev driving operation. N

Fig. 4 is aitransverse section immediately to the rear of the staple holding device with the parts in the position shown in Fig. 1.

Fig. 5 is a similar view with the parts in the position shown in Fig. 2.

Fig. 6 is a similar view with the parts in the position shown in Eig. 3.

Fig. 7 is a detailed view substantially on line 7-7 of Fig. 3, but showing a plurality' 9-9 of Fig. 3.

Fig. 10 is a sectional line 10-10 of Fig. 2.

Fig. 11 is an end view of the slide.

Fig. 12 is a top plan view of the forward end of the slide, and

Fig. 13 is a sectional view through the forward end of the housing showing the slide and plunger in elevation, but showing the effect secured without the use of the staple holding device. f

The machine disclosed comprises the usual base 10 mounted on suitable rubber or fibre supports 1l and carrying the anvil 12 adapted to coact with 4the plunger for clinching the staplespin the usual manner. The

base is provided` adjacent the other end thereof with upwardly extending spaced ears 13 between which is nivoted the slide 14 by any suitable means such as a pin 15, this slide providing a support and guide for the staple strip, as indicated -at 16.

This slide is mounted in the lower part of the housing 17 and secured4 therein by suitable means such as transverse pins or rivets 18. At the forward end of the housing are vertical grooves 19 forming guides-for the plunger 20, and also forming the raceway or throat at the forward eind of the slide-for guiding the individual staples to the anvil after they are severed from the strip, the plunger having longitudinal ribs 21 guided in these grooves and this plunger is so arranged that the lower end 22 thereof coacts lwith the forward upper edge 23 of the slide 14 to sever these individual staples from the strip as the plunger is forced downwardly. z vllVithin the housing above the slide are mounted the usual staple strip feeding and holding mechanism. In the present instance the feeding and holding mechanism comprises a cam plate 24 pivoted at 25 and having spaced lugs 26 and 27 adapted to be engaged by a lug 28 on the plunger as the plunger 1s reciprocated to rock the cam plate on a pivot and move the feed pawl 29 back and forth. This feed pawl is pivoted to the cam plate, as shown at 30, and has `fingers at its forward end to engage between the individual staples in the usual manner. Be-

neath this feed pawland straddled thereby is a holdback 31 pivoted at 32 and also provided at its forward edge with fingers view substantially on adapted to engage the rear side of the`r individual staples to prevent backward movement of the staple strip as the feed pawl is moved backwardly. The feed pawlr and holdback are held in engagement with the staple strip bj the free arms 33 and 34 of a wire spring mounted on a vpin 35. The cam plate may be provided with a slot 36 through which may extend a pin 37 to-act as a stop for the cam plate especially to assist in asf sembling.

Secured to the upper end of the plunger is the usual hand knob 38 by which ,the plunger is forced downwardly for the staple setting operation, and between this knob and the top ofthe housing :is the yusual coiled spring 39 tendingto.l retain the plunger in its uppermost position, and to automatically return it to this`position after the staple has been set. l

Engaging .the rear ofthe plunger and movable with the same throughout a certain portion of its travel is a staple holding and straightening device indicated as a whole at 40. This device has two L-shaped ngers 41 spaced so as to straddle the connection between two staples on the strip, and to extend down between the first and second staple when the first staple is in severing position, the transversely extending parts 42 of these fingers being positioned between the prongs of the first and second staples and the longitudinally extending portions 43 being positioned'just outside these prongs so as to prevent the staple bending backwardly under the pressure of the plunger during the' severing operation, and also to guide the staple after it is cut to prevent its wobbling or turning out of position in the raceway and insuring that it reaches the paper in the upright position, and'thus will e properly driven. If the first staple happens to be bent rearwardly on the strip thesefingers will engage the prongs thereof and straighten it prior to the severing roperation.

This element is operated as follows:

The lateral ribs 21 on the plunger are recessed to provide' shoulders 44 which, under certain conditions, are adapted to engage the upper ends of the spring fingers 45 at the upper end of the straightening element 40, the fingers 41 of this element being connectedby the cross-bar 46. The angle shaped fingers 41 engage on the outside and rear of the ribs 21 and slide within the vertical grooves 19 with the plunger for a portion of its movement. On the top of the housing about the plunger is mounted a cam plate 47 having lugs 48 extending under the spring fingers 45. When the plunger is in its uppermost position, as shown in Fig. 4, the lower edge of the cross-bar 46 rests on the top of lug 28 carried by the plunger with the ends of the fingers 45 beneath the shoulders 44 and the lower end of fingers 4L are spaced above the top of the staple strip. A blow on the 'knob 38 will depress the plu-nger and` through the action on the shoulders 44 and spring fingers 45 will move the straightener element 4() down with the plunger. At the time the plunger and straightener reach theV together carrying the severed staple along' with them, and the plunger will drive the prongs of this staple through the paper and in coaction with the anvil 12 will clinch the same. On the downward movement of these elements, however, soon after the staple is severed, the lugs 48 on the cam plate 47 will engage under the curved part of the fingers 45, and will move the upper` ends thereof outwardly from engagement with the shoulders 44 at about the time or just before the lower end of the fingers 41 engage the top of the anvil, as shown in Fig. 6. At this time the plunger has not yet reached the top ofthe anvil and this action of the lugs 48 will thus disconnect the straightener from the plunger and allow the plunger to move through the rest of its travel to clinch the staple while the straightener remains stationary. After the staple has been set and pressure removed from the top of the plunger the spring 39 will raise the plunger to its uppermost position ready for the next operation. As the plunger moves upwardly from its lowermost position the straightener 40 'will remain stationary until the lug 28 on the plunger engages the underside of the cross-bar 26 then the straightener will move upwardly with the plunger. On the latter part of the downward movement of the plungerthe lug 28 engages the cam lug 27 on the cam plate 24 moving the feed pawl 29 rearwardly over the next staple. When the plunger returns to its uppermost position, the lug 28 engages the upper lug 26 on cam plate 24 moving the feed pawl forwardly a distance equalto that between two adjacent staples, and advances the staple strip on the slide 14 to' bring the next staple to severing position under the plunger. Dur ing the backward movement of the feed lpawl the hold back 31 prevents the staple strip moving backwardly with the feed pawl.

The slide '14 for supporting and guiding the staple strip is ofl a width on its upper lfll) cated at 50 and is of a width somewhat greater than the outside width of the sta le. It will thus be seen the staple strip is guided by and has free movement along lthe up er part of the slide. In the drawing the outslde portions of the lower part 50 of the slide are shown integral with the same and act as spacing elements to properly position the slide in the housing 17, lbut these side portions may obviously be made of separate fiat strips of suitable thickness if desired, or may be formed on the housing, their purpose being to provide clearance spaces between the sides of the slide 14 and the housing at the upper part of the slide to allow passage of the prongs of the staples. l

It has been found in practice that sometimes yunder careless operation, especially if the plunger is depressed more than once with no work to be attached beneath the plunger or without moving this work, that one or more staples may be jammed in the lower part of the raceway. Also when the straightener andholder 40 is not employed, after the cutting edges of the plunger and slide become somewhat dulled'a staple may be bent backwardly, as indicated in Fig. 13, and if the plunger is depressed the single staple might become jammed in the raceway and clou the machine. -In order to facilitate freeing of the machine under these conditions I have4 terminated the spacing elements 51 at a distance from the forward end of the slide as shown at 52, or in the form shown have cut away the. forward portion of the same to provide afree space beneath the staples on the opposite sides of this slide. for the entire height ofithis slide at the forward end thereof, as shown at 52, and the thickness off this part of the slide is not greater than the distance between the prongs of the staples. In other words there is a clearance space provided on each side of the slide for the entire height thereof at its forward end between this slide and the walls of the housing and at the rear of the staple straightener to provide clearance for the staple prongs and allow the staples to drop or be easily forced out the lower end ofthe raceway should they become bent out of shape or wedged therein. This clearance space for the staple prongs should preferably extend rearwardly) from the front edge of the slide for supporting the staple strip a distance substantially equal to the length of the prongs for the very best results. because then `.no matter how "much the staple is bent it will not clog.

However. as in actual practice the staples are very seldom bent backwardly to the extreme position but usually only a small amount, any clearance for these prongs back of the fingers 41 of the staple straightening and holding device greater than the thickness or gauge of the metal forming the prongs is a decided advantage in reducing the liability of the staples to bind in the raceway, because in jamming there is a tendency for the prongs to turn at right angles or transversely of the strip and these clearance spaces prevent their wedging in the guideways. Therefore, the greater the distance these clearance spaces extend to the rear of the straightening and holding device, or to` a machine not provided with such clearance spaces. The front end of the spacing elements should preferably be spaced from the end of the slide a distance about equal to the length of the prongs of the staples when no straightener 40 is used although this distance is.not lineal and may vary considerably and may be considerably less than this amount especially if it is used with the straightening element 40. I also, in addition, preferably bevel 0E somewhat the opposite vertical edges of the front end of the slide as shown at 53.

Referring to Figs. 7 and 8 I have shown.

two staples clinched on each other in the raceway, by way of illustration, although the mechanism will operate in the same manner with more of these staples. If there is no work beneath the plunger, these staples will be jammed in the raceway, and especially between the forward walls of the grooves 19 and lower portions of the fingers 41, as shown in Fig. 7. Ifl now the plunger is moved upwardly to its uppermost position the ngers 41 will bewithdrawn from the jammed staples, as shown in Fig. 8, and because of the space at the rear of the same on the opposite sides of the forward end of the slide 14 between it and the inner walls of the housing, these staples are loosened and in most instances will drop out as soon as the forward end of the housing is raised above the anvil. If, however, they do not drop out of their own accord they are suliiciently loosened that if the knob 88 is struck a sharp blow with the anvil and housing separated the lingers 4l will push the jammed staples out of the raceway completely clearing the' machine.

In Fig. 13 the slide 14 is the same as that used in the other combination with the forward ends of the spacing elements 51 spaced from the forward end of the slide to provide space at the opposite sides of the lower portion of the front end of the slide. With this layout the straightening and holding mechanism .'40 is not used, so that there is nothing to .positively hold this staple in its verticalposition during the severing operation. It -it should be bent, however, as indicated in Fig. 13, the space at the forward end of the spacing elements 51 allows the prongs to swing backwardly and the staple will not become jammed in the raceway.

To assist in the clearing operation I also preferv to cut away slightlyr the forward side of the lower ends of the groove-S19, as shown at 54.

It has been foundI in operation that by spacing the ends of the spacing elements or vsides 51 4away from the lingers of the staple straightening and holding means in a manner disclosed above clogging of the machine is eifectively prevented, as any staple which is not properly driven will either drop out of the raceway of its own accord or will be so loose in the same that it may be easily removed to clear the machine even when a large number of these staples are driven one after another and on to each other in the 4 raceway.

The clearance spaces at the sides of the slide at the forward end thereof also prevents breakage of nthe staple straightening and holding device 40. For instance suppose the prongs of the forward or `first staple should bebent backward, as shown in Fig. 13. Inthis position if the spacing elements 51 extended to the forward Iend of the slide the ends of the prongs would rest on the top surface of these spacing elements. Then if the plunger and meinber 40 are depressed the fingers 41 must either cut the prongs of the staple or the straightening and holding device will be broken because the tops of the members 51 prevent the staple moving to the vertical posit-ion.y With the clearancek spaces, however, there is nothing to prevent the staple straightening, so that the staple will be moved to the proper position by the fingers 41 and then severed from the strip and set the saine as if it had not been bent. However, as stated above, any clearance spaces greater than the thickness of the staple prongs for the staple prongs back of the straightening .and holdin device is a decided advantage over machines not having these clearance spaces.

Having thus set forth the nati'ire of my invention, what I claim 1. In a strip staple machine, the combination with a slide for holding. and guiding a staple strip, a plunger coacting with the forwa'rd end of the slide to sever the individual staples, means for advancing the staple strip to bring the staples successively to severing position, and means adapted to enter between the prongs of the first and second sta-- ples during the severing and clinching operation to hold the saine, the forward end of the slide being so arranged and proportioned that there is a clearance space or the staple 'prongs on both sides of the slide extending position, and iingersfoperated'by the plung` er adapted for insertion between the prongs of the first and second staples to hold .the

saine during the severing and driving operation, the forward end of the slide being so proportioned and arranged as to provide on each of the opposite sides thereof a clearance space for the staple prongs after the staple has left the severing position, /said clearance spaces being of a reater width than the thickness o/f the stap e pron and located immediately to the rear of said fingers when they are in the holding position.

3. In a stapling machine, in combination, a staple strip carrying bar, a staple stri feeding means, means adapted to be insert from above the staple strip between the prongs of two adjacent staples to straighten the saine on the strip, and spacing means at the sides of the bar at the lower portion thereof to provide spaces for movement of the staple prongs at the upper part of the bar, said spacing means terminating a distance greater than the thickness of the sta le prongs to the rear of`thestraightening evicev to provide clearance spaces for the staple prongs immediately to the rear of the straightening device when it is in its lowest position.`

4; In a stapling machine, in combination, astaple strip carrying bar, a staple strip feeding means, and staple straightening means comprising fingers mounted so as to be insertable between the prongs of two adjacent staples rfrom above the strip to straighten the staples on the strip, there be ing clearance spaces for the staple prongs on the sides ofthe bar at the forward end thereof extending throughout the height of the bar, said clearance spaces being of a greater width than the thickness of the staple prongs and located immediately to the rear of said fingers, when theyare in their lowest position..

'5. In a stapling machine, in combination, a staple strip carrying bar, a staple strip feeding means, and staple straightening means comprising fingers adapted to be inserted between theJ prongs of two adjacent staples to straighten the same upon the 13 strip, there being clearance spaces for the staple prongs on the sides of the bar at the forward end thereof located immediately throughout the height of the bar, said clear-v ance spaces being of a width greater thanv the thickness of the staplel prongs and extending tothe rea-r of the said fingers when they are between the Staples.

6. In a strip staple machine, a slide for supporting the staple strip, a plunger arranged to coact with the forward end of the slide to cut the individual staples from the strip and to set said staples, and staple straightening and holding means arranged to be inserted between the prongs of the first and second staples on the strip, there being clearance spaces for the staple prongs at the sides of said slide at the forward endl thereof extending throughout the height of the slide and extending rearwardly from said straightenin g and holding means when said means is in thc holding position a distance greater' than the thickness' of the staple prongs.

7. In a strip staple machine, a slide for supporting the staple strip, a plunger arranged to coaot with the forward end of said slide to cut the individual staples from the strip, and staple straightening'and holding means operated by said plunger comprising fingers ladapted to be inserted `be.- tween the -prongs of the irst and second staples on the strip and downwardly from above the strip, there being clearance spaces for the staple prongs on opposite sides of said slide at the forward end thereof exl tending throughout the height of the slide and extending rearwardlybfrom said fingers when they are in the holding position a distance greater than the thickness of the o staple prongs.

8. In a stapling machine, in combination, a staple strip carrying bar, a staple strip feeding means, and staple straightening means comprising fingers mounted so as to be insertable between the prongs of two adjacent staples from above the strip to straighten the staples on the strip, there being clearance spaces for the st-aple prongs on the sides of the bar at the forward yend supporting the staple strip, a plunger arranged to leoact with the forward end of said slide to cut the individual staplesrfrom the strip, and staple straightening and holding means operated by said plunger comprising fingers adapted to vbe'inserted between the prongs of the first and second staples on the strip and downwardly from above the strip, there being clearance spaces .66

for the' staple prongs on opposite sides of said slide at the for-ward endl thereof extending throughout the height of the slide and extendingrearwardly beyond said iingers when they are in the holding position K a distance not less than substantially the length of the staple prongs. y

In testimony whereof aix my signaf ture.

FRIDOLIN POLZER. 

